High radiance light emitting diode (LED) light sources are in high demand for challenging applications in surgical and microscopy lighting. Prior art in the surgical and microscopy lighting fields typically utilize tungsten or tungsten halogen, metal halide, short arc xenon lamps, short arc mercury lamps, or more recently, systems incorporating pre-packaged high brightness white LEDs. The tungsten halogen sources do not have sufficient radiance for many of the more demanding surgical applications and have very short life on the order of only hundreds of hours or less. Metal halide, short arc xenon lamps and short arc mercury lamps require high voltage on the order of tens of kilovolts to initiate the arc, which can be an issue relative to EMI concerns in the operating room. The arc lamps also suffer from arc flicker which necessitates homogenizing optics which further reduces the source radiance. Furthermore, the metal halide, xenon and mercury lamps use toxic mercury which is being forced out of the market by regulatory agencies due to toxicity concerns. LED based surgical illumination sources offer the benefits of long life and high radiance, but commercially available units suffer from very low CRI on the order of 65 to 80 and do not have user adjustable CCT. Additionally, since they are typically made out of white LED die only, the CCT generally increases with increasing intensity and thus is not stable.